Discordant Fluctuation:

As you can see, the ToolTip states that every "offensive magical ability" should generate a "backlash" from DF. On Live, this aura was doing exactly that, providing "backlash" for every single target spell and every AoE or DoT used against the Chosen AND his groupmates within 100 feet. This was very quickly found to be way out of control, so the DEV Team at the time nerfed the ability. It appears that now, DF will only backlash on Direct Attacks. The DoTs and AoEs do not appear to be triggering this ability.
By now you are probably wondering why I bothered to write this because that seems "fair" . I submit that, in the state of the game today, there needs to be a balancing of the damage output to the backlash. In other words, in LIVE, the pendulum swung way too far and the nerf bat was way too big. In the image below, you will see my DF backlash hit once, while the BW hits me 7 times. You must understand, I have over-capped resistances that most players do not. Without my resistances, the damage output from the BW would have been even greater, while my measly backlash is easily managed by one tick of one HoT from a healer. I am not looking to equal the damage output with an aura, but I am looking to make it matter. A t this time, DF is fluff damage. It needs to have its teeth back.

I suggest you leave BW class alone, and empower the Chosen to play the role he was originally designed to play in the Discord Tree - party protector and counter spellcaster. Allow DF to backlash on every magical attack. In the image above the BW does over 2200 damage (after mitigation - without, over 5500 damage) with 2 direct attacks and 3 smaller DoTs. If DF provided a backlash for the initial hit of every offensive magical ability, for every group member BUT only ticked once per attack (not ticking on subsequent ticks of DoTs just the initial one) I would still have only done roughly 1200 damage. While nothing to sneeze at, it is substantial damage that can't be laughed off with one tick of the basic healers' HoT. I feel this would balance the Chosen class back to where we need to be in this age of BW Bomb groups and 3 hour keep gate skirmishes.
Look at the damage total for the average chosen in scenarios. Do you really think countering the #1 dps class with a minimal buff to the #5 dps class will tip the scales too far in the other direction? I don't think so. I think it's time we quit nerfing top damage dealers and started finding small buffs to bring the other classes back in line with the top end classes.
TLDR: Change Discordant Fluctuation to "tick" or "Backlash" on every first hit of offensive magical abilities used on all team mates again; however, do not allow it to "Tick" or "Backlash" on subsequent damage from DoT abilities or AoE abilities.